You make it sound like the chemistry and physic systems are something optional the developers added on top of the game, while the truth is that they were the very core of the game and were present even before anything else was done. There was a prototype of BotW with Zelda1 graphics were Link could cut a tree, use it to cross water, set it on fire...and this was the first thing that was done when development started, long very any work started on the story, map, combat or traversal systems...
Clearly
@Gingerbread Man is referring to games that try to look realistic through their graphics, artstyle, animations....That's not the case with BotW or TotK. They aren't trying to be realistic, they are trying to be FUN. Kill a wolf and it turns into a steak, pet a horse and hearts will fly out of it. Everything is abstracted to trim out all the fat and make a beeline towards the fun. And this applies to the physics system as well, they're simplified in a way that they react like we expect them to, but they throw away all the complexity so we can just focus on the fun instead of on the number of freckles and details per square centimeter on the cheek of the main character.